Computer-aided Analysis Of Building Height And Visibility

The planning and design of the ancient town and ancient buildings, the protection of historical landscape and spatial patterns without destroyed is the most important prerequisite. New building has an important influence to the historical landscape and the protected building, has become an important focus of urban and rural planning and design staff.The traditional planning and design are mostly two-dimensional design. When the three-dimensional effect is needed, it is remodeled on other 3D software. The paper uses the topographic map data, builds the 3D urban model in AutoCAD, analyzes the influence of new building to the landscape style, researches and implements the new building height and visibility analysis, provides a new virtual visualization design method for urban and rural planning, could assist conservation planning of ancient urban landscape, to achieve a three-dimensional analysis, scientific decision-making and reduce the cost.. The paper mainly carried out the following work:In order to show visual design results, achieve building height and visibility analysis in the 3D environment, the 3D urban model is established. Using triangulation and solid models, the terrain and building models are constructed and rendered according elevation values. This modeling method is simple and efficient, provides a basic platform for 3D design and analysis, could meet the planning and design about buildings in urban and rural planning.To ensure that new building does not affect the original pattern of the city skyline and urban landscape, designs a new method about building height analysis, constructs the line of sight analysis model with spatial information. On this basis, express visually the new building height analysis results in 3D urban model, implements multi-view, multi-angle visual expression of the surrounding environment after the new building completed.In order to make the new building does not affect the protection of buildings of sight corridor and the surrounding visual field, the spatial occlusion with the terrain and building is studied. A line of sight analysis model is constructed between the protected and the new buildings. With the line of sight Accessibility Theory, the visible and invisible lines are drawn. On the basis, designs the method of the viewshed expression, and the visual analysis results of visibility and viewshed are showed in the three-dimensional urban model.